1. Technical Field
The present invention relates to a radiation image detection apparatus and a radiation image photographing system.
2. Related Art
An X-ray image photographing has been widely distributed in areas such as, for example, medical diagnoses and a non-destructive inspection. In a general X-ray image photographing, an X-ray is irradiated to a subject and attenuated while being transmitted through each part of the subject. The transmitted X-ray is then detected and an X-ray image of the subject is acquired based on the intensity distribution of the transmitted X-ray.
Recently, as for a medium for detecting an X-ray, a flat panel detector (FPD) having a two-dimensional array of pixels that generates an electrical charge when subjected to X-ray irradiation and generating an image data based on an electrical signal output from each pixel of the pixel array has been used. In the X-ray image photographing, a so-called an electronic cassette which is configured to accommodate the FPD in a portable case has been widely used.
Further, there is a known FPD configured to detect X-ray irradiation based on electrical signal output from the pixel (for example, Patent Document 1 (JP-A-2003-126072)). In the FPD disclosed in Patent Document 1, all the pixels are installed to be utilized in both image acquisition and irradiation detection, while in a FPD disclosed in Patent Document 2 (JP-A-2011-174908), a pixel for detecting irradiation is installed separately from a pixel for detecting image.
The FPD configured to detect X-ray irradiation based on electrical signal output from the pixel does not need to be synchronized with an X-ray irradiation apparatus or a console controlling the operation of the X-ray irradiation apparatus and an operability is improved.